/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.runtime.rest.handler.job.checkpoints;

import org.apache.flink.api.common.JobID;
import org.apache.flink.runtime.checkpoint.AbstractCheckpointStats;
import org.apache.flink.runtime.checkpoint.CheckpointStatsHistory;
import org.apache.flink.runtime.checkpoint.CheckpointStatsSnapshot;
import org.apache.flink.runtime.executiongraph.AccessExecutionGraph;
import org.apache.flink.runtime.rest.handler.HandlerRequest;
import org.apache.flink.runtime.rest.messages.EmptyRequestBody;
import org.apache.flink.runtime.rest.messages.JobIDPathParameter;
import org.apache.flink.runtime.rest.messages.MessageHeaders;
import org.apache.flink.runtime.rest.messages.ResponseBody;
import org.apache.flink.runtime.rest.messages.checkpoints.CheckpointIdPathParameter;
import org.apache.flink.runtime.rest.messages.checkpoints.CheckpointMessageParameters;
import org.apache.flink.runtime.rest.messages.checkpoints.CheckpointStatistics;
import org.apache.flink.runtime.webmonitor.RestfulGateway;
import org.apache.flink.runtime.webmonitor.history.ArchivedJson;
import org.apache.flink.runtime.webmonitor.history.OnlyExecutionGraphJsonArchivist;
import org.apache.flink.runtime.webmonitor.retriever.GatewayRetriever;

import org.apache.flink.shaded.guava33.com.google.common.cache.Cache;

import java.io.IOException;
import java.time.Duration;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executor;

/** REST handler which returns the details for a checkpoint. */
public class CheckpointStatisticDetailsHandler
        extends AbstractCheckpointHandler<CheckpointStatistics, CheckpointMessageParameters>
        implements OnlyExecutionGraphJsonArchivist {

    public CheckpointStatisticDetailsHandler(
            GatewayRetriever<? extends RestfulGateway> leaderRetriever,
            Duration timeout,
            Map<String, String> responseHeaders,
            MessageHeaders<EmptyRequestBody, CheckpointStatistics, CheckpointMessageParameters>
                    messageHeaders,
            Executor executor,
            Cache<JobID, CompletableFuture<CheckpointStatsSnapshot>> checkpointStatsSnapshotCache,
            CheckpointStatsCache checkpointStatsCache) {
        super(
                leaderRetriever,
                timeout,
                responseHeaders,
                messageHeaders,
                executor,
                checkpointStatsSnapshotCache,
                checkpointStatsCache);
    }

    @Override
    protected CheckpointStatistics handleCheckpointRequest(
            HandlerRequest<EmptyRequestBody> ignored, AbstractCheckpointStats checkpointStats) {
        return CheckpointStatistics.generateCheckpointStatistics(checkpointStats, true);
    }

    @Override
    public Collection<ArchivedJson> archiveJsonWithPath(AccessExecutionGraph graph)
            throws IOException {
        CheckpointStatsSnapshot stats = graph.getCheckpointStatsSnapshot();
        if (stats == null) {
            return Collections.emptyList();
        }
        CheckpointStatsHistory history = stats.getHistory();
        List<ArchivedJson> archive = new ArrayList<>(history.getCheckpoints().size());
        for (AbstractCheckpointStats checkpoint : history.getCheckpoints()) {
            ResponseBody json = CheckpointStatistics.generateCheckpointStatistics(checkpoint, true);
            String path =
                    getMessageHeaders()
                            .getTargetRestEndpointURL()
                            .replace(':' + JobIDPathParameter.KEY, graph.getJobID().toString())
                            .replace(
                                    ':' + CheckpointIdPathParameter.KEY,
                                    String.valueOf(checkpoint.getCheckpointId()));
            archive.add(new ArchivedJson(path, json));
        }
        return archive;
    }
}
